Python json list as json and write in json file,tkinter popup as messagebox

import uuid
import datetime
import time
import json
import tkinter as tk
import tkinter.messagebox as msgBox

class Book():
    def __init__(self,id,name,isbn,comment,content,summary,title,topic):
        self.id=id
        self.name=name
        self.isbn=isbn
        self.comment=comment
        self.content=content
        self.summary=summary
        self.title=title
        self.topic=topic

    def __str__(self):
        return f'Id:{self.id},name:{self.name},isbn:{self.isbn},comment:{self.comment},content:{self.content},summary:{self.summary},title:{self.title},topic:{self.topic}'

book_list=[]

arr=range(1,100001)
for a in arr:
    book_list.append(Book(f'{a}',f'Name_{a}',f'ISBN_{a}',f'Comment_{a}',f'Content_{a}',f'Summary_{a}',f'Title_{a}',f'Topic_{a}'))

book_data=[]
for bk in book_list:
    dic={
        'id':bk.id,
        'name':bk.name,
        'isbn':bk.isbn,
        'comment':bk.comment,
        'content':bk.content,
        'summary':bk.summary,
        'title':bk.title,
        'topic':bk.topic
    }
    book_data.append(dic)

jsonFile=f'Json_{datetime.datetime.now().strftime("%Y%m%d%H%M%S%f")}.json'
with open(jsonFile,'a+',encoding='utf-8') as jsonWriteFile:
    json.dump(book_data,jsonWriteFile,indent=4)

msgBox.showinfo(f'json serialization finished!',f'{datetime.datetime.now()} save {len(book_list)} items in {jsonFile}')